Studies on pectin. Part II

Abstract

A method of estimation of pectin is described, based on the principle put forward by Carre and Haynes, but with several important modifications vitally affecting accuracy. By a process of differential extraction it is possible not only to obtain figures for total pectin content, but also for the individual groups[long dash]water soluble pectin, or "pectinogen," pectin in combination with metallic ions, or "protopectin," and combined pectic acid, or pectates. Figures are given for certain leaves, fruits, and cereal grains. Pectin in the cereal grains is almost entirely present as pectate, while in certain fruits, such as apple, orange and lemon, the water soluble form is preponderant.